Supervised electric system



May 7,' 1935. H. c. GRANT. JR

SUPERVISED ELECTRIC SYSTEM Filed March 8, 1928 Patented May 7; I935UNITED STATES PATENT OFFICE sornvrsan anaemic srs'rau Application Marc]:8, 1928, Serial No. 259,958 '0 Claims. (oi. 111-455) This inventionrelates to alarm systems, for iire,.burglary, etc., in which athermostat or other circuit closer is connected across the two mainleads of the electric alarm, and a resistance 5 is connected across themain leads beyond the circuit closer or series circuit closers, so thatunder normal conditions a supervisory current flows through theresistance and the trouble relay serving to energize the trouble relaywhich 10 normally holds open the circuit of the trouble alarm, whileupon the operation of a thermostat or other circuit closer the fullcurrent causes the alarm relay to close the circuit of the main alarmthrough flre, burglary, or other principal 15 alarm. In case 01'derangement of the alarm continue to ring until the trouble is cleared,or the bell circuit is opened manually. It the bell circuit is openedthere is no certainty that it will be closed again after the trouble iscleared and 30 there may be thereafter, therefore, no supervision oi'the remaining circuits, that is, no means by which derangement of suchother circuits will be indicated. The purpose in view in the presentinvention is to overcome these practical diillculties in the operationof the system and to provid means whereby the particular circuit whichhas become deranged shall be indicated and shall continue to beindicated by a visual indicator even after the audible trouble alarm orbell has been stopped. and whereby the audible alarm orbellshallcontinuetobesoconnectedastosound on the derangement 01 anyother circuit. The invention will be more fully explained hereinafterwith reference to the accompanying drawing in which:

l 'lgure l is a diagrammatic representation 01 an alarm systemconstructed and arranged in accordance with the invention.

Figure 2 is a similar view illustrating a modiii cation.

In the system shown the battery it is connected through a feeder b withthe main leads c 01' the several local circuits, of which two arerepresented. Thermostats or circuit closers d, of which-there may beseveral in each local circults is deranged. Furthermore, the bell willcuit, are connected across the main leads 0, c and outside of the mostremote circuit closera resistance e is also connected across the mainleads. The return lead 0 oi each local circuit, including an alarm lampor "other visual indica- 5 tor c, is connected by a wire 0 through thecoils oi an underload trouble relay I, back to the return leg b oi themain circuit, which includes the coils of an overload or main alarmrelay 0 which I controls the alarm circuit and for convenience may becalled the alarm relay to distinguish it from the trouble relay abovementioned.

When the system is in normal condition, with no circuit closer closed,the current which flows through the resistance e and the coils of thetrouble relay 1 is suflicient to energize the relay I but is notsufilcient to energize the relay 0 which has a diirerent winding. Eachtrouble relay 1 controls two contacts! and I. both being connected onone side, through the wire I, with the return leg b 01' the maincircuit. The armatures or movable contacts I and f cooperaterespectively with contacts I and I, the former of which is connected bya wire I, including a local visual indicator, such as a lamp f", withthe main leads 26 c of each local circuit. The other contact 1 isconnected through a wire I and an audible alarm," such as a bell f, withthe leg b of the main circuit. At f in each line 1 is a switch, manuallycontrolled and of the usual toggle variety, inca- 30 pable of remainingin an intermediate position, which serves to connect the line i, withits visual indicator I", either with the relay controlled contact f orwith the main lead 0 c or each local circuit. So long as the system isnormal each local trouble relay f holds the movable contact I away fromthe fixed contact i, butshould the local circuit become deranged so asto prevent the flow of current the relay 1 will release the movablecontacts I and I and permit current to flow through the visual troublesignal f of the corresponding local circuit, and through the audiblesignal I which is common to all of thelocal circuits. The audiblesignal, it it be a bell, will continue to ring until the break in thelocal circuit is repaired and the relay 1' again picks up the movablecontact or until, as contemplated, the switch f is moved toward the leftto establish connection between the line c -and the line I, thus againcausing 'a current to flow through the relay 1' whereby the relay fpicks up its movable contacts, thereby opening the circuit through theaudible signal I. As a result, the local visual indicator or lamp f'will remain lighted to indicate a derangement 0: the circuit and it willremain lighted even after the local circuit trouble has been repaired,so as to indicate that the local circuit is still cut on from theaudible trouble signal.

I. To extinguish the lamp f' the switch I! is moved toward the right toestablish connection with the fixed contact I Since the local circuittrouble has been repaired, current will again flow through the relay Iso that the movable contacts will remain up and the local circuit willagain be in condition to indicate derangement. The relay 0 is notenergized by the current which fiows when the system is in normalcondition, but it any one of the circuit closers d in any of the localcircuits is operated, as by the outbreak of fire or the intrusion of aburglar, the resistance e will be short circuited and the current willflow, energizing the relay 0 and causing it to pick up its armature ormovable contact a and close the circuit through the fixed contact a andthrough the line a and main audible alarm or bell a convenientlyreferred to as the fire alarm. The current, under these conditions, alsooperates the corresponding local circuit visual indicator or lamp c.

It will be seen that the system, as described, will indicate which ofany number of local circuits is deranged, and will permit the commonaudible circuit alarm or bell to be stopped by bypassing the currentthrough the trouble relay I and causing it to pick up its armatures andso open the circuit to the bell, and will not cut out.

the bell in any local circuitother than that in which trouble has beenindicated, the bell in every other local circuit being always soconnected as to operate in the event of derangement of that localcircuit. Alter the break in the local circuit has been repaired the lampI in that circuit will remain lighted when the local relay is againenergized and will remain lighted thereafter until the switch 1 isthrown to the right to interrupt the current through the lamp.

It will be seen that the modified system shown in Figure 2 is identicalwith that shown in Figure 1 except for the-arrangement of each visualindicator f and corresponding switch I with respect to the relay I andits contacts I and I, as the parts are shown in Figure 1. In thesystemas shown in Figure 2 each trouble relay I controls two contacts I and Iwhich cooperate respectively with contacts I and I the former I beingconnected, as before, by a wire I through a lamp I with the main leads cof the local circuit, the-other, I being connected, as before, through awire I and bell I with the leg b of the main circuit. The manuallycontrolled toggle switch I is in this instance connected into the leg Iand is adapted to establish connection therefrom either to the terminalI of the wire I or with the heel I 0! the contact I". With thisarrangement, in the event of failure of the supervisory current in thelocal circuit, as for example, by the breaking of a wire, the relay Iwill be de-energized, allowing its armatures to close the contacts at Iand I whereby circuits are closed through the trouble lamp I of thecorresponding local circuit and the trouble alarm I. The circuit throughthe trouble alarm bell may be opened by moving the switch I to the leftto establish contact at the point I. The lamp I remains lighted evenduring the movement of the switch I because of the contact establishedat the'point I. As soon as the derangement of the local circuit isrepaired the relay I will be energized and will pick up its movablecontacts, but the lamp I will continue to be lighted by reason of theconnection estabarrangement shown in Figure '1 current is bypassedthrough the lamp I'! and the relay I. A further diflerence is that withthe arrangement shown in Figure 2 the lamp I remains lighted even whilethe switch I is being moved from one contact to the other, while withthe arrangement shown in Figure l the lamp I" is temporarilyextinguished during the movement of the switch.

I claim as my invention:

1. In an electric alarm system of the type wherein'a plurality ofcircuits are provided each of whichincludes a source 0! electricalenergy and a relay 'coil, the combination of two circuits controlled byeach relay and independent of the plurality of circuits, one of each ofthe last named circuits including signalling means of a substantiallynon-objectionable. nature to the senses, and the other thereof includingsignalling means having a signalling eilect of a nature objectionable tothe senses, and a switch and connections to close the circuit through afirst signalling means and disconnect the second signalling means fromactuation by a particular local circuit whilst leaving the secondsignalling means connected for actuation by any one of the remaininglocal circuits, said connections maintaining the circuit through thefirst signalling means closed until the last named switch is opened.

2. In an electric alarm system of the type wherein a plurality ofcircuits are provided each.

of which includes a source of electrical energy and a relay coil, thecombination of two circuits controlled by each relay'and independent ofthe plurality of circuits one of each of the last named circuitsincluding signalling means of a substantially non-objectionable natureto the senses, and the other thereof including signalling means having asignalling effect oi a nature objectionable to the senses, and a switchand connections to close the circuit through a relay and a firstsignalling means and disconnect the second signalling means fromactuation by a particular local circuit whilst leaving the secondsignalling means connected for actuation by any one of the remaininglocal circuits, said connections maintaining the circuit through thefirst signalling means closed .until the last named switch is opened.

3. In an electric alarm system of the type including signalling meanshaving a signalling ef-' fect of a nature objectionable to the senses,circuit closing means in the last named circuits operated by saidrelays, and additional circuit clostbminfrom thenbe ing means in acircuit including a first signalling means to maintain the firstsignalling means in" an energized condition and disconnect the sec andsignalling means from actuation by a particular local circuit whilstleaving the second signalling means connected for actuation by any oneof the remaining local circuits, said connections maintaining thecircuit through the first signalling means closed until the last namedclosing means is opened.

4. In an electric alarm system of the type wherein a plurality ofcircuits are provided each of which includes a source of electricalenergy and a .relay coil, the combination of auxiliary circuitscontrolled by the relay coils including signalling means of asubstantially non-objectionable nature to the senses, second circuitscontrolled by the relay coils including signalling means having asignalling eflect of a nature obiectionable to the senses, circuitclosing means in the last named circuits operated by said relays,additional circuit closing means in the auxiliary circuits including thefirst signalling means and including means to efiect deenergization 01'the second signalling means with respect to a particular local circuitwhilst leaving the second signalling means connected for actuation byany one of the remaining local circuits and to maintain the firstsignalling means in energized condition, said connections maintainingthe circuit through the first signalling means closed until the lastnamed closing means is opened.

5. In an electric alarm system of the type wherein a plurality oi localcircuits are provided each of which includes a source of current and arelay coil, and having a visual signal for each local circuit and anaudible signal common to all of the local circuits, the combination attwo circults controlled by each relay, a visual signal in one of thecircuits and the audible signal in the other of the circuits, a switch,and connections to disconnect the audible signal from actuation by aparticular local circuit and to maintain the connection to a visualsignal corresponding to the relay that has operated closed, the audiblesignal remaining connected for actuation by any one of the remaininglocal circuits, said connections maintaining the circuit through thefirst signalling means closed until the last named switch is opened.

6. In an electric alarm system 0! the type wherein a plurality of localcircuits are provided each or which includes a source oi. electricalenergy and a relay coil, the combination of a plurality of auxiliarycircuits each including independent signalling means of a substantiallynonobjectionable nature to the senses, a plurality of second auxiliarycircuits including common signalling means having a signalling eflect o!a nature objectionable to the senses, all said auxiliary circuits beingindependent of the plurality 01 local circuits, circuit closing means inthe auxiliary circuits including the first signalling means includingmeans to disconnect the second signalling means with respect to aparticular local circuit, said closing means maintaining the circuitthrough the first signalling means closed until opened.

HARRY CAMPBELL GRANT, Jr.

